Test switch



Sept. 8, 1931 J. E. BABER 1,822,866

TEST SWITCH Filed July 5, 192 1 3 Sheets-Sheet 2 James E'. Haber Sept. 8, 1931. Q J BABER 1,822,866

TEST SWITCH Filed July 5, 1928 3 Sheets-Sheet 3 09 a Z1 5 I 103 m2:-

QWIQ/ A? Z 7 Emu tor 17122215 5 E. Haber Patented Sept. 8, 1931 UNITED STATES PATENT @FFECE TEST SWITCH Application filed July 5, 1928.

The invention forming the subject matter of this application is a relay test switch of the drum type designed to facilitate the testing of a relay only when the power circuit controlling the relay is broken.

The main object of the invention is to provide a relay with a switch rotatable to a predetermined position to close the circuit between the relay and the source of energy normally operating it; and also rotatable to a second predetermined position to break said circuit and to expose contact terminals adapted to be connected up to and independent .source of energy, including various testing instruments in its circuit.

Another object of the invention is to provide a switch of this type with a safety device to prevent access tothe test contact terminals at all times when the relay is in circuit with its normally operating source of energy.

A further object is to provide switches of this type with a locking element, which may be sealed, to prevent unauthorized operation of the switch.

Other objects of the invention will become apparent as the detailed description thereof proceeds.

In the accompanying drawings:

Fig. 1 is a diagrammatic layout of the switch with its parts relatively positioned for connection to the testing apparatus, which is also illustrated diagrammatically in this figure;

Fig. 2 is a diagrammatic layout of the switch illustrating the parts thereof relatively arranged to close the circuit between a relay and its operating source of energy;

Fig. 3 is an elevation of one side of the switch as installed on a switch board;

Fig. 4 is a top plan of the switch as shown in Fig. 3;

Fig. 5 is an elevation of the other side of said switch, with parts of the switch operating mechanism broken away and shown in section;

Fig. 6 is a bottom plan View of a cap for operating the switch;

Fig. 7 is a vertical section on the line 77 of Fig. 4;

Fig. 8 is a fragmentary sectional detail of Serial No. 290,579.

a sealing and locking device for preventing unauthorized operation of the switch;

Fig. 9 is a central vertical section of the switch, showing the contact elements thereof relatively rotated to break the relay-operating circuit and to position the switch operating cap to permit connection of the relay with the testing apparatus;

Fig. 10 is a horizontal section taken on the line 1010 of Fig. 9;

Fig. 11 is a vertical section taken on the line 1111 of Fig. 9, with the part of the shaft carrying the conducting segments shown in elevation;

Fig. 12 is a fragmentary detail vertical section taken on line 1212 of Fig. 10;

Fig. 13 is a central vertical section similar to Fig. 9, but showing the contact elements rotated to place the relay in circuit with the main control lines;

Fig. 1 1 is a fragmentary vertical section taken on line 1 1 14 of Fig. 15;

Fig. 15 is a fragmentary top plan view of the switch with the contact elements arranged in the normal relay operating position shown in Fig. 13, part of the switch operating cap and plug closure plate being broken away to disclose the structure more clearly;

Fig. 16 is a horizontal section taken on the line 1616 of Fig. 12;

Fig. 17 is a horizontal section taken on the line 1717 of Fig; 13;

Fig. 18 is a horizontal section taken on the line 18-18 of Fig. 9; and

Fig. 19 is a horizontal section on line 1919 of Fig. 5.

Referring now to the drawings:

The switch (see Figs. 11 and 13) elements are designed to be assembled on aninsulated switch panel or plate 1 which is suitably bored to receive various contact elements of the switch and, in effect,- forms a part of the switch.

' The switch proper comprises acylindrical shaft 2, mounted to rotate in a bearing aperture 3, bored through the panel 1. The shaft 2' is provided with a shoulder 1 adapted to seat against the rear face of panel 1, and limit the lengthwise movement of the shaft relative to said panel. A shoulder 5 is also formed on shaft 2 to seat against an annular block 6 of bakelite or any suitable insulating fiber or other material.

The block 6 is centrally bored to fit the shaft 2 between the shoulders 4 and 5, and is held against the rear side of panel 1 by four contact elements 7, 8, 9 and 10, (see Figs. 3, 5, 9 and 18) which are screwthreaded to receive, and be held against the rear side of panel 1, by the screw threaded ends of test contact sockets 11, 12, 13 and 14, respectively.

Each of the test sockets 11, 12, 13 and 14 (see Figs. and 7) comprises a body 15 axially bored to form a plug receiving bore 16, and having flange 17 formed at the bored end to seat against the front face of panel 1. The body 15 is reduced for about one-half of its length to form a cylindrical stem 18 coaxial with bore 16, and this stem has its end screwthreaded to engage the correspondingly screwthreaded bore 19 of one of the contact elements 7, 8, 9 or 10.

The bored end of each socket 11, 12, 13 and 14 is provided with diametrically opposite slots 20 and 21 (see Fig. 15) adapted to receive a screwdriver, or similar tool, to turn the socket when it is desired to connect it with one of the elements, 7, 8, 9 or 10.

The elements 7, 8, 9 and 10 are seated in slots 22, 23, 24 and 25, respectively, (Fig. 18) cut radially in the edge of the block 6; and each element is provided with a lip 26 which overlaps the rear face of block 6 and holdsthe latter tight against the rear side of panel 1 when the elements are screwed up tight thereon by the sockets 11, 12, 13 and 14.

'The block 6 forms a support for a cylindrical casing 27 of fiber or other insulating material having its upper edge provided with notches 28, 29, '30 and 31 to fit snugly over,

and be flush'w'ith the outer faces of the elements 7 8, 9 and 10. The other end of casing'27 fits snugly over, and is suitably secured to a cylindrical disk 32 which forms a step bearing for the shaft 2 and is centrally bored to form a bearing for the reduced end 33 of shaft 2.

Machine screws 34 suitably spaced around the ends of casing 27 are tapped into block 6 and disk 32 to hold the casing 27, disk 32 and shaft'2 assembled on the panel 1.

The shoulder 35, on the lower end of shaft 2 and impinging lightly against the inner face of disk 32, and the shoulder 4 prevent axial movement of said shaft 2 relative to the panel 1.

A tube 36 of bakelite or other insulating fiber is pinned to shaft 2 to rotate therewith, and has a row of contact plates 37, 38, 39 and 40, suitably secured thereto, and in axial alinement along said tube 36. These contact plates are segments of a cylinder somewhat'greater than a quadrant. The shaft 2 is designed to rotate through an angle of substantially 90 degrees, and the contact plates are made to correspond with this turning limit.

In order to limit rotation of the shaft 2, the disk 32 (see Figs. 9, 13 and 17) has stop pins 41 and 42 secured thereto and a pin 43 is secured radially to shaft 2 to contact with one or the other of the pins 41 and 42 to limit the rotation of shaft 2 in either direction.

The casing 27 is provided with a removable section 27 detachably secured at one end to disk 32 by a machine screw 44 (see Fig. 5), and, at its other end by a screw 45 screwthreaded into block 6. A slot 46 is formed in the upper end of section 27 to facilitate removal of the segment by sliding movement thereof under the contact plates 48 and 49, which overlap the joints between the casing 27 and its section 27. The removable section is provided, in order to give access to the various elements inside the casing, either for the purpose of assembling or replacing them.

On the outside of the casing 27, and on the relay. side of the switch, four contact bands 48, 49, 50 and 51 have their upper ends connected electrically to the contact elements 10, 7, Sand 9, respectively; and have their lower ends'connected by contact screws 52, 53, 54 and to curved contact springs 56, 57, 58 and 59, respectively, on the inside of the easing on the screws 52, 53, 54 and 55.

Nuts 60, 61, 62 and 63 clamp the bands 48, 49, 50 and 51 and the contact springs 56, 57, 58 and 59 respectively, to the casing 27; and lock nuts 64, 65, 66 and 67 on these screws clamp the terminals ofthe relay wires 68, 69, 70 and 71, electrically to the bands 48, 49, 50 and 51 and the contact springs 56, 57, 58 and 59, respectively.

The contact springs 56, 57, 58 and 59'are adapted to contact with the contact segments 37, 38, 39 and 40, respectively, to conduct current to the relay elements from the normal source of electrical energy through the spring contacts 7 2-, 73, 74 and 75, respectively.

The control bus 76' is connected to contact spring by means of the contact bolt 77, (see Fig. 3) the nut 78, and lock nut 79. The trip coil line 80 is similarly connected by bolt 81, nut 82 and lock nut 83 to the spring contact plate 74.

Lines 84 and 85 connect opposite ends of the transformer secondary 86 to the contact plates 73 and 72, by means of the contact bolts 87 and 88, respectively, and lock and clamping nuts similar to those of the other contact bolts.

As so far described, four pairs of spring contact plates are mounted within the cas ing 27 to cooperate with the contact segments 37, 38, 39 and 40 that they are in constant contact with the spring contacts 72, 73, 74 and 75, respectively, throughout the limits of rotation of shaft 2. At one of the limits of rotation of shaft 2, these segments separate from the spring contact plates 56, 57, 58 and 59 (see Fig. 9) and break the circuit between the relay elements and the operating source of energy. As shown in Figs. 2, 11 and 13, the transformer contact segment 37 is L-shaped with a recess 89 formed therein adjacent the transformer side of the switch. An odd spring contact plate 90 is secured to the casing 27 'o'fby a clamp bolt 91 and a nut 92; and a conductor 93 (Figs. 1, 2 and 3) taps the line 84 leading from one end of transformer secondary 86. These parts are so designed and relatively mounted that the vertical leg 37 510f segment 37 makes contact with the spring contact plate 90, only when the circuit is broken between the relay and its source of normal operation, the circuit of secondary 86 of the transformer being therefore closed 61211; all times.

The switch is shown in Figs. 1, 9, and 11 with the shaft rotated tobreak circuit between the relay and its normal source of operating energy. This is the position in 53which the sockets 11, 12, 13 and 14 are exposed to receive plugs connected up to the testing apparatus in order to test the relay R. In order to control access to these sockets and to operate the switch, the shaft 2 is exaugtended beyond the front side of the switch panel 1, and is provided with a key slot 94, in which a key 95 projecting into the bore 96 of a cap 97 is adapted to slide. The cap 97 is provided with a set screw 98 to lock the cap securely to shaft 2.

The cap 97 has suitably secured thereto a cup 99, of bakelite or other suitable insulating material, and this cup is provided with four openings 100, 101, 102 and 103, adapted to register with the sockets 11, 12, 13 and 14 in either the circuit breaking or circuit closing positions determined by the stop pins 41 and 42 on disk 32 at the bottom of shaft 2.

In order to prevent access to the sockets 11, :12, 13 and 14, except when the shaft 2 is positioned as shown in Fig. 9, a disk 104 is rotatably mounted on the shaft 2 between the cup 99 and the switch panel 1. This disk 104 has four openings 105, 106, 107 and 108, 0 "also adapted to register with the sockets, 11, 12,13 and 14. The cup- 99, however, is capable of rotation through an angle of 90 degrees; but the disk 104 is limited to rotation of 45 degrees; and the parts are so arranged that the openings 100, 101, 102, 103, 105, 106, 107 and 108 are alined with the sockets 11, 12, 13 and 14 only when the circuit to the relay through segments 37, 38, 39 and is broken as shown in Fig. 9. In this position the test plugs 109, 110, 111, and 112 can be inserted into the sockets 11, 12, 13 and 14 in order to test the relay R, as shown in Fig. 1.

The testing apparatus connected to the plugs 109, 110, 111 and 112 forms no part of the present invention and need not be described in detail, as its general character will be evident from inspection of Fig. 1 of the drawings.

By reference to Figs. 10 and 16, it will be seen that the disk 104 is provided with arouate slots 113 and 114 each of which starts substantially on a diameter of the disk, and extends for 45 degrees toward the other slot. A .pin 115, on the insulating block 116, secured to panel 1, extends into slot 114; and a similar pin 117 fixed to the cup 99, extends into the slot 113.

The lost motion operation of disk 104 is illustrated clearly in Figs. 16 and 10. In Fig. 16 the disk 104 is shown in position where it blocks access to sockets 11, 12, 13 and 14, and to which position it was drawn by contact of pin 117 with one end of slot 113. In this position when the cup 99 is rotated anti-clockwise, as seen in Fig. 16, the pin 113, carried by the cup for the first 45 degrees of its rotation moves through the slot 113, without rotating the disk 104. At the end of the first 45 degrees of rotation, the pin 117 engages the other end of slot 113, and drags the disk 104 with it through an angle of 45 degrees until the disk 104 is stopped by pin 115 engaging the other end of the slot 114.

It will be seen from Figs. 10 and 16 that when the sockets 11, 12, 13 and 14 are exposed the pins 115 and 117 are diametrically opposite each other, and that the pin 115 is the stop pin, while pin 117 is the disk moving pin.

In order to look the disk 104 and the switch in the non-test position, the cup 99 is provided with a fifth hole 118, equidistant from the adjacent plug receiving holes 102 and 103 of the cup 99. When'the disk 104 is in the locking position, this hole 118 will register with one of the holes in the disk 104, but will be out of registry with the sockets under the disk. A pin 119 (see Figs. 5 and 8) may then be inserted in hole 118 and in the hole of the disk 104 in registry therewith, and a sealing wire 120 may be passed through an aperture therein and through the aperture 121 in bracket 122, fixed to cup 99, to lock the cup 99 and disk 104 against unauthorized operations It will be obvious from Fig. 1, that when the switch shaft 2 is rotated to break the circuit between the relay R and its normal operating circuit, the energy for operating and testing the relay is derived through the testing apparatus connected to test plugs 109, 110, 111 and 113.

The switch is fool-proof; it presents a dead front when the relay is in normal operation; and no connection can be made for testing the relay until the normal operating circuit is broken; thereby preventing accidental tripping of the circuit breaker. The switch cannot be closed until all test plugs are removed therefrom. Any relay, in a system using a plurality of relays, can be tested while the others and their circuit are in operation,

arotatable switch interposed between said and these other relays still protect their part of the circuit. 1

WVhat I claim is: 1.. A relay, meansfor operating said relay,

means and relay, means for rotating said switch to-make and break the circuit between said operating means and relay, a relaytesting device, and means-to prevent connection m between said device and relay by presenting tween: said operating means and relay, are-- la-y testing device, and means to prevent connection of said device to said' relay when the a dead front to the connecting contact-s of'said device when said circuit is closed.

2; A relay,:means for operating said relay,

a; switch for-making and breaking circuit becircuitisclosed.

31 A relay, means'for operat ing said relay, switch rotatabl'evto: make and break circuit between said means and relay, stops for limiting' the rotation: of: said switch through apredetermined arc in either direction, a relaytesting device, and means rotatable with sai'd switch to prevent connection between said deviceand relay when the latter is'inone of its stopped: positions.

4 A switch panel, a relay, inean's for operating said relay, a shaft rotatable on said panel about an axis perpendicular tosaid" panehand liaving'insulated contact segments thereon to make and break the circuit between: said means and relay, contact blocks extending through said panel concentrically with. said shaft, a relay testing device adapted: to be connected to said blocks, and means rotatable on said shaft to prevent connectionbetween said device and blocks- I when; the said circuit is closed;

5.. A switch panel, a relay, means for operating said relay, a shaft ext'ending perpendicularly through said panel and havinga-- part thereof insulated, contact segments spaced along said insulated part, a cylin-- device, and means to prevent connection between said device and" relay when the segments are in contact with all of said contact elements.

6.. A. relay, means for-operating said re lay; a panel board, a shaft'ext'en'ding perpen-- dicularly through; said board", a series of cylindrical contact? sockets extending through said, board concentric withsaid shaft, and insulated casing fixed tov said board concen 3 trio with said? shaft, cooperating contacts -on' ments connected'tosaidrelay, a relay testing said casing and shaft to make and break the circuit between said means and relay, a relaytesting device inCludingcontact plugs adapt ed to seat in said sockets, and means operable by rotation of saidshaft to preventinsertion of said plugs in said sockets when said circuit is'cl'osed'.v

' 7. A relay, means foroperati'n'g said relay, a panel, a cylindrical casing fixed perpendicularly to one side of said panel, a shaft concentric with said casing extending perpendicularly through and on opposite sides of said panel, cooperating contact elements on said shaft and casing to make and break the circuit between said relay and means, contact blocks extending concentrically with said shaft through said panel and connected to the relay contact elements only, a relay test device adapted to be connected to said blocks, and means operable by rotation of said shaft to prevent connection of said device to said blocks when the said circuit is closed.

8. A1 relay, apanel board, means for opcrating said relay, a switch interposed between said relay and sa-id' means rotatably mounted on said board, contact terminals connected to said relay and extending tlirouglisaid board to the face thereof, a cap for rotating said switch and having apertures therethrough adapted to aline with said terminals in twopredetermined" positions of said switch, a. disk interposed between said cap-and board and rotatable with said shaft and having 'aperturestherethrough adapted to ali'ne-with said terminals and the apertures in said cap; and means on said board and capto move said disk soto close communication between said cap aper tures and terminals when the switch is in circuit breaking position.

9; A relay, means for operating said re lay, a panel board, a set of contact element'sconnectedtosaid relay, :1: second set-'of contact elements connected tosaid means, a

switch rotatable on said panel to make and" break the circuit througlisaid elements from" said means to said relay, means extending connected to said relay, contactterminals extending through said panel board andcon nected"to said eleinents; a relay testingdevice,

means-for connecting said device to said terminals, a switclrrotatable'1nt0 and out of contact 'witli said elements-to :make and break the circuit between said meansand said re-- lay,.and means operable by rotation of said switch to prevent connection of said device to said terminals when the switch is in circuit closing position.

11. A relay having a set of contact elements connected thereto, a second set of contact elements spaced from the first named set, means connected to the second set of contact elements for operating said relay, a panel board, a switch rotatable thereon to connect and disconnect electrically the two sets of elements, a cup shaped disk rotatable on the face of the panel board and adapted to rotate said switch, said disk having apertures therethrough adapted to expose the first named set of elements, means for limiting the rotation of said switch in opposite directions, and means interposed between said disks and panel board and rotatable to a limited extent in opposite directions to prevent access to the first named set of elements when the two sets of elements are electrically connected.

12. A panel board, a cylindrical casing fixed to and extending perpendicularly from one side of said board, a shaft concentrically mounted in said casing and extending through said board and beyond the front thereof, cooperating contact elements spaced apart and mounted on said shaft and casing, contact terminals extending concentrically with said shaft from one face of said board to the other and connected to some of said elements, a cup covering said terminals and fixed to said shaft to rotate the latter and having apertures therethrough adapted to expose said terminals, means for limiting the rotation of said shaft through an angle of 90 degrees, a disk in said cup rotatable on said shaft and provided with apertures adapted to aline with the apertures in said cup, and a lost motion connection between said cup, board and disk to limit the move ment of said disk through an angle of 45 degrees in either direction to cause alinement of the apertures in said cup and disk with said terminals only when the circuit between said elements is open.

18. A switch comprising a plate, a shaft rotatable about an axis perpendicular to said plate and having insulated contact segments thereon, a casing fixed to said plate concentric with said shaft and having spaced apart contact elements thereon adapted to contact with said segments, contact blocks connected to said elements and extending through'said plate, said blocks being formed as sockets adapted to receive the contact plugs of'a testing device, and means rotatable on said shaft to prevent connection between said plugs and blocks when said segments are in contact with all of said elements.

14:. A switch comprising a plate, a shaft extending perpendicularly through said plate, a series of cylindrical contact sockets extending through said plate concentric with said shaft and adapted to receive removable contact plugs, an insulated casing fixed to said plate concentric with said shaft, cooperating contacts on said casing and shaft to make and break a circuit, and means operable by rotation of said shaft to prevent insertion of said plugs in said sockets when the said circuit is closed.

15. A switch comprising a plate, a cylindrical casing fixed perpendicularly to one side of said plate, a shaft concentric with said casingand extending perpendicularly through said casing on opposite sides of said plate, cooperating sets of contact elements on said shaft and casing to make and break a circuit, contact blocks extending concentrically with said shaft through said plate and connected to one set of said elements, and means operable by rotation of said shaft to prevent access to one side of said blocks when the said circuit is closed.

16. A plate, a shaft rotatably mounted on said plate, a support connected to said plate, cooperating sets of contact elements on said shaft and support, contact terminals connected to one set of said elements on said support and extending through said plate to the face thereof, a cap for rotating said shaft and having apertures therethrough adapted to aline with said terminals in two predetermined positions of said shaft, a disk interposed between said cap and plate and rotatable with said shaft and adapted to aline with said terminals and the apertures in said cap, and means on the plate and cap to move said disk so as to close communication be tween said cap apertures and terminals when the switch is in circuit closing position.

17. A plate, a shaft rotatable thereon, two sets of contact elements supported by said plate and spaced apart from each other, contact segments on said shaft adapted to connect and dis-connect electrically, said two sets of elements, a cup shaped disk rotatable on one face ofsaid plate and adapted to rotate said shaft, said disk having apertures therethrough adapted to expose one of said sets of contact elements, means for limiting the rotation of said shaft in opposite directions, and means interposed between said disk and plate and rotatable in opposite directions to a limited extent to prevent access to the said set of elements when the two sets are electrically connected by said segments.

, In testimony whereof I affix my signature.

JAMES EARL BABER. 

